The present invention relates generally to the game of golf, and has particular reference to an improved sighting device for assisting players to determine correct putting directions on sloping putting greens.
As is well known to those acquainted with the game of golf, putting greens are rarely level, being intentionally sloped in most instances for drainage reasons. Because greens slope and roll and have subtle breaks, a golf ball lying on the green and putted directly towards the cup will seldom go in. Thus, depending on the direction and amount of slope, the ball usually must be aimed to the left or right of the cup in order to have the ball drop in.
To gauge the direction and degree of slope in a putting green, many golfers use the putter as a plumb bob sighting device by holding the handle at arm's length between thumb and forefinger whereby the club assumes a vertical position due to the weight of the club head. In addition to this method, a number of portable sighting devices have been developed for golfers and those known to the applicant are disclosed in U.S. Pat. Nos. 2,724,898; 3,293,755; 3,535,792 and 3,870,299.
Of these, U.S. No. Pat. 3,293,755 to Cronwell is believed to be the closest to the present invention in that it utilizes a pendulum pointer that operates as a plumb bob. To use the Cronwell device, however, it must first be laid flat on the green and aligned with the cup, then rolled upwardly to allow the pendulum to assume its gravity dictated position in which position it is locked, then rolled back down flat on the green where the pendulum points in the direction that the ball should be propelled.
Other related prior art developed in a preliminary search consists of U.S. Pat. Nos. 396,883 and 2,754,594 and Danish Pat. No. 15752 of Mar. 18, 1912.